1. Field of the Invention
The present invention relates to reaction solution dot shape information obtainment method to be employed for a transfer type inkjet recording method.
2. Description of the Related Art
As one of printing methods, a recording method (transfer type inkjet recording method), in which an intermediate image is formed by discharging an ink by an inkjet recording method onto an intermediate transfer member to which a reaction solution is applied, and a final image is formed by transferring the formed intermediate image onto a recording medium, has been known. In the transfer type inject recording method, when a large amount of the reaction solution, particularly, the reaction solution in such an amount that exceeds a diameter of one ink dot to be formed on the intermediate transfer member, is applied onto the intermediate transfer member, a force by which the intermediate image adheres to the intermediate transfer member is reduced, which sometimes disturbs the transferred image. Therefore, in the transfer type inkjet recording method, it is important to apply the reaction solution in an amount that is sufficient to avoid a reduction in viscosity or an aggregation effect.
Japanese Patent Application Laid-Open No. 2002-370441 discusses a transfer type inkjet recording method, wherein an application amount of a reaction solution is reduced to be less than an application amount of an ink by reducing a discharge amount per dot of the reaction solution or performing intermittent discharge of the reaction solution.
In the transfer type inkjet recording method, it is necessary to bring the applied reaction solution and the ink into contact with each other without fail on an image forming surface of the intermediate transfer member. Since the image forming surface of the intermediate transfer member has high ink releasability in the transfer to the recording medium, the reaction solution is prevented from easily wetting and spreading on the image forming surface of the intermediate transfer member. As a result, when the application amount of the reaction solution is reduced as discussed in Japanese Patent Application Laid-Open No. 2002-370441, there is a possibility that a part in which the reaction solution and the ink do not contact with each other is generated due to repelled reaction solution or landing position shift between the reaction solution and the ink on the image forming surface of the intermediate transfer member. When the reaction solution and the ink do not contact with each other, the part becomes a region in which the ink and the reaction solution do not react with each other. An image of the non-reaction region is disturbed in the transfer, which causes image deterioration in some cases. Therefore, an application amount of the reaction solution can be optimized based on a state of the applied reaction solution if the state of the applied reaction solution is detected. Particularly, since the intermediate transfer member moves a lot in the transfer type inkjet recording method, a dot shape of the reaction solution before the application of the ink is a considerably important element in terms of its influences on the image.
However, since the reaction solution is ordinarily colorless and transparent, it has been difficult to obtain dot shape information of the reaction solution before the ink application.